Building 6mmAI, how long of a barrel?

My new project is a 6mm ackely improved on a savage action. I'm thinking of a 1/9 twist for bullets in the 100gr range. Probably a mcgowan varmint contour barrel with a muzzle brake. The one thing I'm having trouble deciding on is barrel length? How long do I really need? Weight is not a huge issue, but I don't mind having a shorter barrel if I can get away with it.

1/8 twist is also an option. I prefer to go shorter since it will see quite a bit of hunting time. I just want to be long enough to not hinder performance. I just put a .204 together and a lot of guys swear if it was less than 26" you aren't burning all your powder. Whether that is true or not, I can't say. I haven't heard a common number to go with the the 6mmAI.

I shoot heavy VLD's out of all my guns. A 6mmAI just beg's for the 105 (or even the 115) VLD, assuming you plan to do some longer range shooting. The 1/8 twist is the general favorite for this weight range.

Barrel length is a personal preference. A longer barrel will get you more velocity, but might not be the best option for a "hunting" gun. Your style of hunting will dictate what is best for you.

1/8 twist is also an option. I prefer to go shorter since it will see quite a bit of hunting time. I just want to be long enough to not hinder performance. I just put a .204 together and a lot of guys swear if it was less than 26" you aren't burning all your powder. Whether that is true or not, I can't say. I haven't heard a common number to go with the the 6mmAI.

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I'd say with a 24" bbl you'll get all the good out of your 6mm AI and have a nice practical hunting length rifle.

As for the .204, my little 20" is certainly getting good powder burn efficiency since it has very little muzzle flash in low light. It just doesn't take much barrel to burn 30-32gr of powder.

If you want to use most of the 100-107 gr bullets you will need a 1 in 8 twist. As for length for a 6mmAI I'd opt for 28". I have a 28" 257 weatherby and that barrel added velocity without being too long for me. Get the barrel long, you can always cut some off and recrown if you find it objectionable.

If weight is a concern just flute the barrel
Or a thinner contour or both.

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Weight isn't really a concern. I have lighter guns if I need them, but I'm also not TRYING to build the heaviest gun I can haha. If a 22'' gun will shoot the same as a 26'' gun, then I have no problem reducing the length and weight of the barrel.

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